Photography
My understanding of Camera's isn't brilliant however after the website http://www.cambridgeincolour.com and some other addtional research was introduce to me I learnt some of the basics.
First off I heard about depth of field, so therefore I researched into what it was to get a greater understanding of the subject.
Depth of field is how the camera sees things depth of field changes depending on the type of camera you use, aperture and focusing distance however there are other aspects that effect the depth of field such as print size and distance.
This diagram is on the website although it is exaggerated, the diagram explains the circle of confusion from what I understand the circle of confusion is what the camera cannot focus therefore is classed as unsharp.
A good circle of confusion is loosely defined as one which you would notice when the picture is enlarged to a standard 8x10 inch print and observed from a viewing distance of 1ft.
A different maximum circle of confusion is applied when you have bigger pixels in you look on this diagram you can see the to the left and right that the focal points are within the depth of field.
Depth of field only sets a maximum value for the circle of confusion and doesn't describe what happens with the regions once they become bokeh. Obviously if you have a different lens the circle of confusion will become bigger or smaller depending on which lens you would use. In reality the circle on confusion isn't a circle until it is very small. When it become large most lens will render it as a polygonal shape.
The next piece of information I am going to research is Exposure.
The research I have done for this is from Wikipedia.
Now from what I understand of exposure is how long something is exposed for this answer is neither wrong or right.
In photography exposure is how much light you allow into the photograph whilst you are taking the photograph.
You can manipulate the amount of light you allow into your photograph by setting how much light you allow into the photograph, because you can do this it means you set the mood of the picture.
A photograph can be described as overexposed or underexposed, this is when it has a loss of detail. When a photo is looking washed out or all white that is known as "blown out highlights". If overexposure causes this effect then underexposure will do the opposite and cause the photograph to look muddy or undistinguished this is commonly known as "blocked up shadows".
On a SLR camera and probably other types of camera there are 2 settings these being automatic and manual. The difference between these 2 are the fact that in manual you can control the aperture (depth of field) and shutter speed to create the desired exposure. You will find that most photographers will use manual settings because of this reason. If you set your camera to Automatic the camera will automatically calculate and adjust the settings to suite the picture.
You can control the exposure time in a camera by the shutter speed and the Illuminati by the lens aperture. If you have a slow shutter speed and greater lens aperture you allow in more light producing higher luminescence scenes with greater exposures.
One of the main principles of exposure is reciprocity. This means if you expose the film or sensor for a long period of time a reciprocally smaller is aperture is required to reduce the amount of light hitting the film obtain the same exposure.
The next bit of research I done was on shutter speed.
Shutter speed is controlled by when a cameras sensor will be open or closed to let light into the camera lens. The shutter speed means how long light is allowed to enter the camera exposure time is the same concept as shutter speed. If you was to have a fast shutter speed you would have a short exposure time, and if you was to have a slow shutter speed you would have a long exposure time.
You can set the shutter speed manually and there is certain types of day you should take into consideration before hand for example.
| Shutter Speed | Typical Examples |
|---|---|
| 1 - 30+ seconds | Specialty night and low-light photos on a tripod |
| 2 - 1/2 second | To add a silky look to flowing water Landscape photos on a tripod for enhanced depth of field |
| 1/2 to 1/30 second | To add motion blur to the background of a moving subject Carefully taken hand-held photos with stabilization |
| 1/50 - 1/100 second | Typical hand-held photos without substantial zoom |
| 1/250 - 1/500 second | To freeze everyday sports/action subject movement Hand-held photos with substantial zoom (telephoto lens) |
| 1/1000 - 1/4000 second | To freeze extremely fast, up-close subject motion |
Shutter speed is one of the most powerful tools you will learn for photography with shutter speed you can freeze and exaggerate the appearance of motion.
I wasn't sure on what aperture was so I went of and looked at http://www.cambridgeincolour.com/tutorials/camera-exposure.htm and learnt what it meant.
Aperture is basically how much light can pass through a camera lens.They are specified as f-stop values these are also known as counter intuitive because the area of opening increases as the f-stop decreases. Photographers will often refer to this as stopping down or opening up their lens all this means is that they are either increasing or decreasing the f-stop value.
Every time the f-stop value halves, the light collecting area quadruples. There is a formula for this, however most people just memorize the f-stop numbers that corresponding to each doubling/halving of light:
| Aperture Setting | Relative Light | Example Shutter Speed |
|---|---|---|
| f/22 | 1X | 16 seconds |
| f/16 | 2X | 8 seconds |
| f/11 | 4X | 4 seconds |
| f/8.0 | 8X | 2 seconds |
| f/5.6 | 16X | 1 second |
| f/4.0 | 32X | 1/2 second |
| f/2.8 | 64X | 1/4 second |
| f/2.0 | 128X | 1/8 second |
| f/1.4 | 256X | 1/15 second |
The above f-stop numbers are all standard options in any camera. However most will allow you to make finer adjustment such as f/3.2 and f/6.3.
A camera's aperture setting is what determines a photo's depth of field. Lower f-stop values correlate with shallower depth of field and higher f-stop values correlate with a large depth of field.
Now there isn't much left for me to cover on the camera basics I don't think so far I have covered the following; Depth of field, Exposure, Shutter Speed and Aperture, next up is ISO Speed.
ISO Speed means how sensitive the camera is to incoming light. It is very similar to shutter speed if correlates 1:1 like the shutter speed does. Although you always want a lower ISO speed since having a high ISO speed increases image noise.
There isn't much more on ISO Speed although common ISO speeds are 100,200, 400 an 800 these are just the most common speeds a lot of cameras will permit either higher or lower values.
You get this affect as a result of high ISO Speeds
You get this affect as a result of a low ISO speed
As you can see from the 2 images the bottom one has a lot less noise then the top one which is why the lower the shutter speed the better the quality on the photo.
This is the end of this blog post, from this research that I have done on this post I have learnt a lot about depth of field, aperture, exposure, shutter speed and ISO speed. My next post will be about audio I will be researching into frequency and what sound is I will be explaining how it works and what the properties are of sound. I shall then be looking what types of microphones there are and what pick up patterns are around.
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